Osmosis
by suchlostcreatures
Summary: In which Ben doesn't reach Rey in time. (Reylo. Tros AU. Angst with a hopeful ending. Written for the Reylo Fanfiction Anthology fic exchange.)


_Note: Written for viajeramyra for the Reylo Fanfiction Anthology fic exchange on AO3 using the fic prompt __"role reversal - and angst with a happy ending".  
Alternative ending to TROS where Ben doesn't reach Rey in time to stop her from striking down Palpatine._

_I would have done more with this story, if I hadn't had a deadline to write for. Though it's just as well, given my tendency to leave stories hanging! (I'm still working on Conversations, btw.)_

* * *

**OSMOSIS**

**by acowlorsomething aka suchlostcreatures**

The sky falls.

Thousands of ships rain from the stratosphere. Their burning wreckage lighting the sky like brilliant beacons.

_They were the sparks that ignited the flames that burnt the entire Resistance to the ground_, Rey thinks, staring up at the tiny trailing flares. Pinpoints in the sky. Flash fires against the darkness.

She closes her eyes. Watches with her mind's eye as each and every thread of life, thin and insignificant, winks out.

"Motes of dust," she whispers. Her voice too quiet to leave an echo. "Dead. All of them."

All of them.

But one.

"Rey?"

His voice comes to her as a plea across the chasm. An entreat. A hopeless cause.

She pulls her gaze from the sky. The ships have all but gone. Fallen to ash. Ruined upon the landscape of Exegol.

"You're too late." She steps over the body of her fallen grandfather and lowers herself onto the throne. Fingers pressing against the sharply-honed obsidian. Until they bleed.

Bursts of static discharge cast the great amphitheatre in blinding strobes of blue. Illuminating the faceless ones. The cowled ones. The wraiths that cling to the edges. Their words rising and falling in a seamless chant.

Undeterred, he draws near. Three steps. Four. She wonders how many steps he must take before he sees her for what she's become.

The guards form a semi-circle at his back, awaiting her instruction. A wave of her finger has them pulling back into the shadows.

He's no threat. She has the power of the Sith within her. She _is _the Sith.

Seven steps. Then, finally, "Rey, what have you done?"

What has she done? She has stopped the war. She has claimed her birthright. She has found her belonging.

**Pledge yourself, child. Complete your initiation.** _**Strike him down**._

The ink-black whisper passes over her mind like an oil slick. She shudders. At the lubricous discomfort of the presence within her. At the residue it leaves. But she holds her tongue against the vow.

"Rey, look at me." The man before her persists. "Please?"

Who is he, she wonders. Kylo Ren? He who was the hand of a dead Emperor? Albeit unwitting?

No. Kylo Ren would be standing beside her; not before her, seeking to supplicate. So it is the boy he once was. Ben Solo. Thinking to save her.

**Pathetic**.

It is not her own thought, but that of the presence. And it makes her bristle to have thoughts not of her own making, seeding within her head.

**Strike him down. **The presence drops all ruse of gentle compulsion. It clamps and squeezes. Seeking to bend her to its own will. **Show him your strength. Your power. Show him that which he once coveted. Use it to crush him.._._**

She grits her teeth. She will not be bent. She will not be broken. She is the Sith. _She _is the Sith.

"Get out." The words hiss between her teeth.

"No." The reply is soft. Steady. Human. "Not without you."

Her eyes slide to the man. Ben Solo. The blood across his brow. As if his face is determined to seek new scars to replace the old.

"You don't understand what I've done." The presence shifts and squeezes as she speaks. Her fingers clench against the obsidian. "What I've had to do."

"I do." His gaze is unwavering. His eyes are haunted by shadows. "I of all people understand."

She allows an imperceptible nod. Of course, he does. He's lived with this presence for longer than she has lived years. Perhaps he could be of some use after all.

"I don't need Ben Solo," she states, rising from the throne. Her steps are slow and deliberate as she stalks towards him. "I need Kylo Ren."

Distantly, she notes the irony.

And then she offers him her hand.

* * *

Ben stares. There is a compulsion within him to enfold those slender fingers within his own. To grasp what he has longed for harder than he has longed for all else, and crush it to him. Never letting go.

For a moment he imagines a reality where he reaches Rey in time to stand at her side. Where together they destroy the old Emperor and the curse that destroyed their families. He imagines a reality where they're free to carve their own future. Begin their own family. He sees it. So clear…

And that compulsion stirs again. Coaxing him. Assuring him he could have it still, should he just reach out and take her hand...

It is the small escaping groan of his own want that brings Ben back to himself. Snapping him to the here and now, where it is a Palpatine that desires their union - not a ferocious little desert nobody with the spark of rebellion in her heart.

She watches him still, awaiting his decision. A half-smile playing upon her lips as if she knows the answer in advance. Sees his longing. Those sweet _could have beens._

Old anger flares within him. He reaches through the Force to plunge his conscience into her own. He will _wrench_ this parasite from her. He will find the thread that is _Rey_. And pull it back to him.

But the corruption he feels is thick and pressing, and as he tests the strength of the bond they once shared, he feels the darkness within her gaze back. Cool and vast and all-consuming. And utterly nonplussed by his efforts.

He pulls away, recoiling from the terrible truth of what he finds. Exhausted by his own effort.

"Join me." She urges softly, interrupting his mental ransacking with half-lidded eyes. "_Please_."

It is the lilt on that last word that catches him. He raises his gaze with a snap, searching the woman before him as if he might somehow see that spark. That gritty determination. Something to tell him Rey is still in there. In there, and _fighting_.

But the stare that meets him is cool. Indifferent.

What stands before him is a shell. A vessel. It has a heart that beats. It breathes. It lives. But if any of Rey exists within it still, she's hidden deep away. From him. From herself. From whatever has slithered into her consciousness and made itself at home.

Ben steels himself. Fingers knotting into fists at his sides as he holds his ground. For all the years that he has succumbed, unknowingly, to the manipulations of Palpatine, nothing enrages him as much as seeing Rey, once his counterpart in the light, now swallowed whole by this dark corruption.

Nothing wrenches at him as much as knowing _he_ is no longer the monster.

She is.

* * *

"Very well." The shell that once was Rey withdraws her hand and steps back, an empty smile touching her lips.

"Exile yourself to a nameless planet. Hide from the remnants of the Resistance. The First Order. The everyday men and woman you so-recently sought to dominate and oppress. All will seek to hold you accountable."

She watches and waits as he holds himself unflinching against her words. Ah, but there it is; the traitorous tic beneath his eye. The tell that betrays the war raging within him. He may think himself resolute, but the conflict within him is as strong now as it ever was. Emotions that have long been pushed and pulled now do so all the harder.

She knows his thoughts. She sees his impossible choice. How can he stand at this creature's side? She - _it_ \- who was once Rey. Who borrows her face. Who simulates her voice. Who wears this pure white garb as if mocking its host.

A crook of her finger draws his attention to the saber at her side. _Anakin's saber_. Ah, she knows his own hand aches with the urge to call it to him - even as he feels the guards close in at his back; their footsteps silent as they shift across the stone floor. Responding to their leader's most subtle command.

He swallows. Hard. Teeth gritting. "I will join you."

She raises a brow as she watches him, knowing the words taste like bile upon his tongue. He will agree to join her. But he will not take her hand.

She nods. It is good enough. For now.

Another subtle gesture. The guards slide back to the fringes.

She steps from the dais, beckoning him to follow her across the amphitheater floor. Knowing without looking that he will. Eyes fixed ahead. Subjugated.

The faceless ones rise to their feet and roar their victory to the vault.

* * *

**Part II**

* * *

_Ben._

The voice stirs him from his sleep. A soft murmur at the cusp of his ear. An exhalation of breath at his hairline.

_Rise._

It is the voice of his mother. His father. His uncle. His grandfather. It is the voice of Rey.

He reaches. Hands clutching at emptiness.

It is nothing. No one. A tease. An echo of a dream. A hollow promise. A madness wrought by grief.

_Ben, rise._

On the thin margin between sleep and awakening, he reaches again. Stretching out with the Force as much as his fingers. Hoping to grasp hold of something tangible. Something familiar. Something that can give him hope.

Or the will, at least, to start another rotation of waking hours upon this damned planet.

There is no day or night on Exegol. Only the cold darkness of deep space, punctured by brilliant strikes of static energy. Were it not for the subterranea, the planet would be abandoned; the static discharge deeming its surface uninhabitable.

It has taken some time for Ben to learn how to sleep on this world. And then, to wake. The problem not being the indistinction from day to night, but the _dreams_.

Dreams that haunt him with their glimpses of what might have been, had one path been chosen over another. The realities that might have unfolded, had one decision been made different.

Dreams that strike him as so solid and real in that moment of awakening… He wonders if he could reach out and press himself through. Project himself somewhere else. _Anywhere_ else.

Ah, but for _Rey. _For Rey, he stays. Her name a balm as much as a curse.

For Rey, he turned to the light. And it will be for Rey that he returns to the dark. If for nothing else, than to kill the husk she has now become.

If only turning to the dark were so easy the second time.

* * *

The Empress braves the planet's surface to stare up at the starless sky.

There is a sense of loss buried deep within her. Though she has no name for it, nor for its cause.

Palpatine promised that by taking his life force into herself, she would have the power of the Sith fleet. The power to save the Resistance. The power to rule; to bring lasting peace to the galaxy.

The presence shifts within her. She shudders at its oily touch. **I did not lie.**

No. He did not lie.

Upon claiming the Sith throne as her own, she did indeed gain the power to save the Resistance. But therein lay the one small detail Palpatine did not tell her. Because upon asorbing his life force into herself, _Rey_ stopped being the person she once was. And the Resistance, by osmosis, stopped being the cause she wished to champion.

And so she let their ships burn. She let them fall from the sky.

**The same sky you gaze upon. **The presence croons. **And look now, how peaceful it is.**

Yes. That same sky she looks to now. Dark and fathomless and unrelenting.

And oh so

_empty_.

The Empress turns away, back to the catacombs that are now her home.

She buries that sense of loss deep within her. So that she might never again find it.

* * *

Ben walks in the footsteps of the Empress. Her shadow. Her dark warrior. Her Hand.

The Sith Eternal leave their whispers hanging in the air like scents upon a breeze. He learns to listen to them. The undisciplined few who speak too freely their thoughts.

He seeks out those who might betray the Empress's rule. If not now, then later.

Ben learns from them, the secrets of Exegol. And in doing so, a part of him pities them. But it is the task of _Kylo Ren_ to separate the wheat from the chaff. And so he does. Feeling the darkness slip deeper into his veins with each cull.

He wears a mask. Not of metal, but of flesh and bone. His expression veiled. His face like granite. It is an easy practice to fall back into. Buring the truth of his intentions.

He suspects the Empress knows the surface of his thoughts, nonetheless.

"Tell me," she says to him one day, touching his arm with a familiarity that makes his skin crawl. "With the Resistance gone, what would Kylo Ren advise we do next?"

Ben considers his words, chewing them as if to try and gauge their taste. Kylo Ren would issue orders to chase down any last threat of insurgency. To cleanse whole villages of such corruption, if need be. Kylo Ren would be reveling in the newfound power at his hands.

"I would advise we lead the fleet to the Core Worlds," he says finally, "to ascertain our rule over the galaxy."

A part of him is surprised she hasn't issued such orders already. Though he holds his tongue against critique.

"I care nothing for the rule of the galaxy."

It is a statement spoken so softly, so unexpectedly, Ben shoots the Empress an unfettered look; his carefully-contrived mask dropping in his surprise.

He notices then, the deep rings beneath her dull eyes. The haunted look upon her tired face. He wonders...

"How many days has it been?" he asks suddenly, desperately. "How many days, since you've slept?"

"Why?" She draws closer then, carved granite closing over her expression. "Do you think there is light within me still? Do you think I struggle? Like you? Ah, Ben Solo..."

She shakes her head, reaching to trace one gentle fingertip across his jawline. "We have changed places, haven't we? I am all of the Sith. And you…"

Her cool fingers slide to the nape of his neck, squeezing as she drags him to her. So that their foreheads touch. Her breath adjusting to match his. Short. Sharp. Pulse exploding beneath her fingers as she slides them to his throat. She reaches deeper then. Pressing her will against his own. Flaying open his mind so that he can hold _nothing_ back.

"You are a trophy, my dear," he hears her whisper as the ink-black darkness consumes him. "And a lodestone around my neck."

* * *

Deep fissures rake Exegol's surface, extending far into the planet's crust. For centuries, Sith loyalists toiled within its fractured depths, in search of a great cosmic power they believed hidden near its core.

They called this power a _vergence_. A concentration of the Force so powerful, it could create anomalies through space-time. Backdoors from one reality to another.

Opportunities to fix what was broken. To start anew.

The Sith Eternal leave their whispers hanging in the air like scents upon a breeze.

Ben learns to listen to them. The undisciplined few who speak too freely their thoughts. He learns their secrets. And enfolds them deep within his heart. Their secrets give him hope.

* * *

_Rey_.

The voice brushes the edges of her conscience. Pulling her from a hollow, restless sleep.

_Rise, Rey._

It is Leia. It is Luke. It is Ben.

It is no one. Nothing. An echo of a nightmare. An empty threat. A madness…

"I am not _Rey_."

The Empress throws herself from her bed. Calls Leia's lightsaber to her hands. Cleaves a path along the corridors. Her mind resolute as she slips into his quarters. Her trophy. Her Force-forsaken _lodestone_.

She casts a long look at the sleeping form raveled amidst blankets. The tousled black hair. The hint of pale skin beneath damp, tangled locks. The dark sunken hollows below long lashes.

She waits for the presence within her to shift. To lay its thoughts atop of hers. Finish him now, she expects it will say. And she wonders if she will comply - nerves firing at the thought of rebellion. And its consequence.

"Get up!" She moves then, dragging the tangle of blankets and limbs to the ground. Quick. Before she can talk herself from it. Before the presence can anticipate her next move. "Get up, now!"

He is wide-eyed as he stumbles to his feet. And then he sees the saber in her hand. And the acceptance in his face is her undoing.

"I know what I have to do," she begins, saber hilt between them. "But I don't know if I have the strength…"

"_Rey_?" Ben breathes her name in fragile wonder, closing the space between them so that the hilt is all that separates them.

"Will you help me?" She utters the words in trembling desperation. Blinks against the open hope in his eyes. The presence begins to stir. To suspect. There's no time...

"Yes." His eyes bore into her as he moves to close his hands around her own. "Anything."

She nods. Drinking in his softened face. Embedding his features into one last memory.

"Find me." She leans in to whisper against his lips.

Together, they thumb the ignition.

* * *

There are secrets upon Exegol. Dark and deep.

Secrets of which even the Emperor was unaware.

But Ben has learned them. And hidden them away inside that locked part of himself where only a _dyad_ can reach.

He runs. From the deep dark Citadel. To the planet's fragmented surface.

He is all of the Jedi.

And when he reaches the edge of the landscape's deepest fissure, he jumps.

* * *

**Part III**

* * *

As the escape pod slides open, Kylo Ren stands immobile, his gaze lost upon the woman who stares back up at him. Doe-eyed and expectant. Trusting that the good she senses in him will somehow prevail.

She clutches the saber in her hands. And extends it towards him. A peace offering.

He takes it. Fingertips brushing her own. Causing a thrill of static energy to pass between them.

On shaky legs he steps back, allowing her to lift herself from the pod. Too preoccupied by his own startled thoughts to offer assistance. Not that she would likely accept it. Stubborn creature that she is.

A stormtrooper steps forward, cuffs in hand. "No," he snaps, raising a hand to halt him.

From the corner of his eyes, he sees Rey tilt her head towards him, and he imagines one of those fine eyebrows raised in question. The back of his neck prickles as he senses a stormtrooper shuffling his feet restlessly behind him; unsure of what to make of his Commander's hesitation.

Sliding his attention towards the turbolift, he takes a deep breath. And in that moment he knows what he must do.

"Follow me," he demands in a rush, grabbing the scavenger's elbow and spinning her towards the second hangar.

At once, the Stormtroopers who now find themselves standing directly in the path of Kylo Ren step to the side; unquestioning despite their confusion.

"Remain here," he commands before sweeping past, his digging fingers still holding fast the girl as she scurries to keep pace with his long strides.

"What's going on?" Rey hisses, wrenching inefficiently at his grasp. "The way you looked at me when the pod opened, I thought you were taking me to -"

"I was." He replies curtly. "And now, I'm not."

He has, he knows, only moments before Snoke senses a disturbance in the invisible threads that bind Master to Apprentice, and sends troopers to intercept them. Even now, Kylo can feel his own discord thrumming through the Force like ill-plucked harp strings.

And then they're at the second hangar bay, veering towards a sleek black craft. And if there's any question as to why Kylo Ren is escorting a Resistance turncoat aboard his own personal command shuttle and firing the vessel up for an unauthorised flight, no one dares to say it aloud.

And certainly, no one tries to stop them.

* * *

"Where are we going?" Rey's voice rises as the sleek starship screams away from the Supremacy. She's taken the position of copilot as if it's the most natural place for her to be, but she's so buoyant, she can hardly keep herself still on the seat. "Are you _really_ going to leave the First Order and join the Resist-"

"Don't be ridiculous." Kylo deadpans. Mouth set in a grim line as he brings up a holoscreen and starts punching in co-ordinates.

Bracing herself for the wobble as the ship slipped into hyperspace, Rey lets out a long-held breath once the stars turn into streamers.

They've made it clear of the Star Destroyer. Without any sign of pursuit.

Kylo Ren can feel Snoke's fury lashing at his mind. Battering against the traitorous barrier he tries to erect against his Master. The Supreme Leader is relentless. Demanding an explanation. Demanding access to his every inner thought and intent. Kylo's hands clench on the control yoke of the shuttle until he hears plasteel crack beneath his grip. Until he feels the warm slender hands of the Jedi close around his own; to prise away his grasp with gentle fingers.

"Ben?" Rey's voice carries to him as if from a distance. "You can let go."

Let go? The question arises voiceless from within his own head. Slowly Kylo opens his eyes, not realising he closed them. He blinks, feeling the volley of Snoke's anger fall short of its mark as the warmth of the girl's touch channels through him. He feels weightless as the tension in the base of his head ebbs away, and he almost wants to close his eyes again from the sheer relief.

Instead, he focuses on the girl, Rey. His gaze sweeps the bright hazel eyes, taking in the perplexed crease of her brow before hovering on the way her delicate mouth forms a half-o in the midst of shaping a new question. Subconsciously, he moistens his lips, blinking as if lost. The flush that rises to her freckle-smattered cheeks beneath his open scrutiny matches the sudden plume of heat he feels beneath his own skin. Confused by his own response, he turns away. To stare unseeing at the streaming ribbons of light beyond the viewport.

"Ben?"

"Yes?" He tenses. At how easily he falls into that name. It has not been his own since he left Luke's temple aflame. But he can't help but respond to it when it slips so softly from her tongue. He almost craves to hear it from her again.

"Where are we going?"

He shakes his head. Something happened when their fingers touched. Something strange and electric and... He can't make sense of it any more than he can make sense of why he's doing this - running away with a scavenger. A Jedi. A girl he hardly knows. And yet… He feels as if he's known her throughout lifetimes.

"First, we're going to stop Snoke." He says, relaxing into the words. It comes to him now, the secret of his once-Master's undoing. And of the puppeteer who pulls his strings. It comes to him, like an awakening from a dream. "And then we're going to end this war."

He pulls his eyes from the galaxy-scape to meet her own. Wide and bright and full of hope. He smiles. It comes easy with her. "Together."

* * *

**Epilogue**

* * *

_Ben settles into the conscience of his former self. He has not gone back as far as he would have liked - not far back enough to save his father. Or the villagers whose deaths he ordered. Or the old man he struck down in anger. Or the dozen more crimes he committed under the guise of Kylo Ren..._

_But he has peered through many doorways within the Vergence; followed the threads of so many potential lives. So many potential endings. And _this_ was the one where finally, they stood a chance of winning._

_He and Rey, they are a Dyad in the Force. It is the weapon of which Palpatine was unaware. The weapon he didn't know how to use, himself. Until now._

_Sometimes it takes one story ending, to create a new beginning._


End file.
